"As soon as violence broke out — in fact, in anticipation of potential violence — we were very clear in saying that violence was unacceptable, that that was not how governments operate with respect to their people," he told reporters at the time.

Obama's opponent in the 2008 presidential election reaches a very different conclusion.

"History will judge this president incredibly harshly, with disdain and scorn for his failure to come to the moral assistance of the 1.5 million Iranians that were demonstrating in the streets of Tehran," Sen. John McCain, R-Ariz., told Morning Edition host Steve Inskeep today. Those demonstrators, McCain said, were "crying out ... literally crying out ... 'Obama, Obama, are you with us?' ... If we had given them some moral support, it might have made some difference."

McCain did add that "the president and the administration have done a pretty good job on sanctions" aimed at pressuring Iran to give up any efforts to develop nuclear weapons.

On another topic, McCain said that the two years' worth of income tax returns that Republican presidential contender Mitt Romney (whom McCain has endorsed) has released are "enough." When McCain was vetting potential running mates, his staff reportedly got 23 years' worth of Romney's tax records. "I never looked at his tax returns," McCain said. "That wasn't my job or my priority."

Much more from Steve's conversation with the senator is due on Friday's Morning Edition. Click here to find an NPR station that broadcasts or streams the show. After the interview airs, we'll add the audio to the top of this post.

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